The present invention relates in general to actuators and more particularly to actuators for dispensing the pressurized contents of a container through an upstanding valve stem releasably securable in a discharge condition with improved operating features.
Modern pneumatic tires are designed for extended use on vehicles, such as automobiles and trucks, over many miles. Regardless of how well these tires are designed, they can still be punctured by sharp objects inadvertently left on the roadway and go flat. When the tire is punctured, the motorist must change the tire if he has a spare or have another tire put on the vehicle. In some instances, it is difficult to change the tire due to the location of the vehicle, such as when the puncture occurs on roadway which is not flat and the vehicle cannot be safely raised with a jack to change the tire. Another instances is dangerous to change the tire, such as for example, when the tire is punctured on a heavily traveled roadway and there is not sufficient space to change the tire safely.
Various tire inflator and sealant products have been developed for both sealing the puncture in a tire and also inflating the tire so that it can be used to resume travel where the tire puncture may be repaired. These tire inflator and sealant products generally include a container having a inflator and sealant composition contained therein under pressure. This composition is releasable through an upstanding valve in the discharge end of the container. These compositions in the container typically include a liquefied gas in a sufficient quantity to re-inflate the tire to a driveable condition and a sealant material for sealing the puncture when introduced into the tire.
An actuator is provided for attachment to the pressurized container to activate the upstanding valve so that the inflator and sealant composition passes through the valve and then through the actuator to a discharge tube attached to the valve on the tire. In operation, the motorist attaches the discharge tube to the valve on the punctured tire and then properly positions the canister to maximize the flow of the inflator and sealant composition into the tire. Some canisters are designed to be actuated in either an up or inverted position, that is with the upright stem in either an upward or inverted, downward position. The motorist then uses his finger to activate the actuator which in turn activates the valve in the pressurized container to release the inflator and sealant composition into the tire.
If the motorist inadvertently or accidentally depresses the actuator before he is ready to inflate and seal the punctured tire, the inflator and sealant composition is not introduced into the tire and the tire inflator and sealant product escapes. Accidental activation of the actuator can also occur in a wide variety of circumstances in handling the pressurized container. Accordingly, it is desirable to provide an actuator which safeguards against inadvertent or accidental actuation of the actuator. In addition, the manufacturing process for assembling the actuator to the container may exert a force on the actuator and it is desirable to provide an actuator which avoids actuation of the actuator during the manufacturing process. On the other hand, it is desirable to provide an actuator that is easy to activate without requiring substantial finger pressure on the actuator to move it from an unactivated to an activated position, while providing an actuator which moves to an unactivated position when the finger pressure is removed from the actuator.
As the motorist actuates or depresses the actuator, the inflator and sealant composition flows into the actuator from the canister valve and proceeds through the discharge tube and then through the valve on the punctured tire into the tire. If the inflator and sealant composition is allowed to escape at the junction between the actuator and the valve on the canister both the inflator and sealant are not introduced into the tire. Accordingly it is desirable to provide an actuator which maintains the connection between the actuator and the valve on the canister so that the inflator and sealant does not escape at that junction.
Once the inflator and sealant composition is flowing into the punctured tire, maintaining finger pressure on the actuator to keep it in an activated condition can be difficult and strenuous for the motorist. Accordingly, it is desirable to provide a latch for holding the actuator in the activated position while the inflator and sealant composition flows into the punctured tire. Since pneumatic tires have a wide variety of sizes and internal volume, different tires require different amounts of inflator and sealant composition. In order to avoid unnecessary use of the inflator and sealant composition and allow the canister to be used in another punctured tire situation, it is desirable to provide an actuator with a latch which is readily releasable when a sufficient amount of inflator and sealant composition has been introduced into the punctured tire.
It is also desirable to provide an actuator which returns to its unactivated position when the latch is released. Occasionally it is desirable to release small amounts of the inflator and sealant composition and accordingly it is desirable to provide an actuator which can manually be activated without using the latch so that when finger pressure is released, the actuator returns to an unactivated position.
The present invention provides the above described desirable features with an improved actuator. The actuator of the present invention is used with a container having an upstanding valve stem with pressurized contents contained therein. The actuator is capable of either continuously or intermittently dispensing the pressurized contents of the container. To achieve this feature, the actuator of the present invention has a generally cylindrical body which is attachable to the container and has a central aperture therethrough for receiving the upstanding valve stem of the container. The central aperture extends generally along a central axis. The pressurized contents of the container is released through the discharge end of the valve stem.
The actuator has a finger tab which is positioned across the central aperture of the body and has a stem receiving aperture for receiving the upstanding valve stem of the container therein. The stem receiving aperture terminates in a valve seat shoulder which contacts the discharge end of the valve stem. The finger tab also has a discharge orifice formed in the side surface of the finger tab. Upon movement of the finger tab to depress and activate the valve stem, the pressurized contents flows through a passageway in the finger tab extending from the valve seat shoulder to the discharge orifice.
To connect the finger tab to the body, the actuator has an hinge portion which allows for movement of the finger tab between an unactuated position in which the valve stem is not actuated and an actuated position in which the valve stem is actuated to release the pressurized contents of the container.
The actuator hinge portion of the present invention provides an actuator that is easy to activate without requiring substantial finger pressure on the actuator to move it from an unactivated to an activated position. The actuator hinge portion has a body connecting portion, and an upright intermediate portion extending in a direction substantially parallel to the longitudinal axis of the body and is separated from the body by notches extending from the top edge of the cylindrical body toward the bottom edge of the cylindrical body to a position below a plane vertical to the central axis and passing through the discharge end of the valve stem when the container is attached to the actuator. The actuator hinge portion also has a finger tab connecting portion connecting the upright intermediate portion to the finger tab. The notches reduce the force required to move the finger tab from the unactuated position to the actuated position.
The actuator of the present invention provides an improved connection between the finger tab and the discharge end of the valve stem which maintains the junction between the actuator and the valve on the canister so that the inflator and sealant does not escape at that junction. This desirable feature is achieved by providing for rotation of the finger tab about an axis which minimizes movement of the valve stem in a direction other than a vertical direction when it is moved between an actuated and unactuated position. By positioning the rotational axis of the finger tab with respect to the actuator body about a rotational axis which is substantially coplanar with the discharge end of the valve stem, when the finger tab is moved between the actuated and unactuated position the discharge end of the valve stem remains in contact with the valve and seat shoulder of the finger tab so that escape of the pressurized contents of the container is minimized. The present invention provides for the path of the finger tab to be more vertical and collinear with the valve stem that it actuates. By following the valve stem line of movement, less actuation force on the finger tab is required and also an improved seal between the valve and the seat shoulder of the finger tab is achieved.
To safeguard against the inadvertent or accidental actuation, the actuator of the present invention has frangible ribs with a base portion formed integrally with the finger tab and a connecting portion formed integrally with the body. The cross-sectional area of the base portion is greater than the cross-sectional area of the connecting portion. The connecting portions of the frangible ribs are frangible by a force of from between 5 to 30 pounds exerted on the finger tab with the base portion remaining connected to the finger tab when the frangible ribs are separated from the actuator body. After the frangible ribs break away from the actuator body they slide against the actuator body to guide the finger tab and reduce lateral movement of the tab as it moves between an actuated and unactuated position or when used with an overcap.
The actuator of the present invention is capable of either continuously or intermittently dispense the pressurized contents of the container. To intermittently dispensing contents of the container, the finger tab is depressed to the actuated position To continuously dispense the pressurized contents of the container, a latch is provided on the body which engages the finger tab when depressed to a latch actuated position slightly beyond the intermittent actuated position and holds the finger tab in the actuated position. The novel latch of the present invention allows the finger tab to be readily released when the desired amount of pressurized contents are released. The hinge portion of the actuator returns the finger tab to an unactivated position when either the latch is released or pressure is removed from the finger tab.